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BlueAKSSS

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Posts posted by BlueAKSSS

  6. 03 Chevy Short Bed W/5.7l Ls1

    in Engine Tech And Modification

    Posted

    REP is always caused by the tune being off. Even if there is a failure in the throttle-by-wire, the PCM will see that there is more/less airmass than 'reasonably expected' and will assume throttle failure. On FI motors it is common that we tune this diagnostic table to maximum values, essentially disabling the feature in the PCM because when you've got a blower you can get a ton of airmass at half-throttle and the PCM decided there must be a malfunction and goes into REP. My point is, the ETC system never 'talks' to the PCM, the PCM has no idea the ETC exists, all it knows is that there is a lot more/less airmass than it was expecting so it pops the REP mode on you. Ultimately, it's a tuning issue.

     

    The malbehaved idle, is all PCM tuning - nobody put in the time or effort to dial-in the idle, and you really can't do that until you dial-in the AFR first so you have an 'unknown quantity' when it comes to your PCM tune.

     

    AFA mail order tunes, things have gotten a lot better in the last couple years. Firstly, most reputable tuners have now amassed huge libraries of customer tunes and it is likely they have already tuned a LS1 with your cam & induction, so they can offer you a very close (if not exact) base tune. Also now there are 'black boxes' that log information from the PCM, you can buy or rent them from your tuner; basically he will instruct you how to drive the truck to log specific data from specific driving situations and then have you upload that data from the black box over the internet, he can then examine the log and email you a tune for a reflash.

     

    Of course you could buy HPT or EFILive and log the data yourself, and hire a tuner to help you read & decide what changes to make in your tune.

     

    Mr. P. :)

     

    Thanks Mr. P! Great info, I'm glad its just as simple as a tuning issue, so I'll check into getting a mail order or just buy HPT or EFILive and do it myself, but that might be a learning curve.... :chevy:

  8. Smell Coolant Outside, Using Alot

    in General SS

    Posted · Edited by Matt* (see edit history)

    :withstupid:

    My truck had this problem you could smell burning coolant outside of the truck while it was running, turned out the heater core inlet hose was cracked ever so slightly and the stock clamp wasn't tight enough causing a leak under pressure. The coolant would drip down on the exhaust manifold/pipe. Replaced the hose and clamp and never used a drop since. Good luck tracking it down, and welcome to the forum! :chevy:

  10. 03 Chevy Short Bed W/5.7l Ls1

    in Engine Tech And Modification

    Posted

    Just get someone to tune your truck... live if possible. It just sounds like it needs a lot of tunning

     

    I don't believe there is anyone in the state of Alaska that can tune really, there are some shops but I don't think there capable of doing it. I think my only option would be mail order, but my question is how dialed in can they get the tune from just a mail order? I was also thinking of getting HP tuners and seeing whats going on with it, since the last owner had started tuning it with that.

    I guess I just thought the only reason it would go the reduced engine power would be something related to the electric throttle body, not the tune?

  11. 03 Chevy Short Bed W/5.7l Ls1

    in Engine Tech And Modification

    Posted

    Bump! Anyone got any ideas on this problem :confused: . The trucks been parked since I posted this basically. It seems to go into reduced engine power mode randomly. It has an LS2 throttle body and intake manifold along with a spear tech box to control the throttle body I believe. Also when the headlight relay is installed the fuel pump doesn't turn on so the truck won't start unless you take out the relay or have the headlights off weird.... :uhoh: I took apart the fuse box expecting to find a short of some kind causing this but all the wires looked perfect.

    Let me know what you guys think...

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